Equifax technology officials failed to implement a fix to a security flaw in March despite being internally instructed to do so, allowing digital thieves to access the personal information of more than 140 million Americans, the company's former CEO said in remarks prepared for his congressional testimony Tuesday.

Former Equifax CEO Richard Smith apologized for the company's catastrophic security breakdown, which may put victims at risk of identity theft for the rest of their lives.

He said in his prepared remarks that the company had internally instructed "applicable personnel" to install a fix to a compromised Web application on March 9, only to discover months later that the fix had never been carried out.

Smith gave no indication why the company's workers failed to install the so-called Apache Struts upgrade.

But by the time the company determined in mid-August that consumer information likely had been stolen, "it became clear that our worst fears had come true and Equifax had experienced a significant breach," Smith said.

"As CEO I was ultimately responsible for what happened on my watch," Smith said. "Equifax was entrusted with Americans’ private data, and we let them down. To each and every person affected by this breach, I am deeply sorry that this occurred."

Smith is set to appear Tuesday before a House subcommittee, where he's expected to face a bipartisan grilling over the fiasco.

He acknowledged that the website and call center capability Equifax established to serve customers following the breach had faltered.

After many consumers faced error messages on the website and couldn't reach anyone at Equifax by phone, Smith said the company has bolstered its capabilities and extended its offer of free identity theft insurance and credit monitoring.

"Still, the rollout of these resources should have been far better, and I regret that the response exacerbated rather than alleviated matters for so many," he said.